A bomb blast shook the prestigious 22-storey Trader’s Hotel in Myanmar’s main city of Yangon yesterday.

The explosion wounded one guest, an American woman, who was taken to hospital.

Curiously, the explosion at Trader’s didn’t happen in a public area of the hotel but in a room on the ninth floor. The injured woman was said to be staying there with her husband and two young children aged 5 and 8. The husband and children were not hurt.

Police later said the blast was caused by a time bomb. They arrested a 27-year-old suspect said to have previously stayed in the hotel room where the blast occurred. He was detained in the southeastern state of Mon on suspicion of causing serious harm to others and breaking the explosives act.

Officials fear the blast could prove to be the latest in a mysterious series of bombings to have hit Myanmar (formerly Burma) in recent days. Unknown assailants have planted several homemade bombs around the country, reportedly killing two people outside Yangon (formerly Rangoon) and hurting three others in the city at the weekend. No one has claimed responsibility.

Traders’ general manager Phillip Couvaras said in a statement that the hotel was working with authorities to establish what happened.

Tourism to Myanmar is booming but tension lies beneath the surface. The country is largely peaceful, and continues to open up to tourism. Bombings have occurred in the past but violence is rare, although the town and seaport of Thandwe, popular with tourists for its Ngapali Beach, was placed under strict curfew earlier this month after rioting mobs burned about 80 houses down.

The violence coincided with a visit by Myanmar’s President Thein Sein to the troubled region. Thandwe is in Rakhine state, where areas are inhabited by stateless Rohingya Muslims, viewed by the government and by many local people as illegal immigrants from neighbouring Bangladesh. Myanmar denies them citizenship and many in predominantly Buddhist Myanmar resent their presence in the country.

The Times of India reports that violence over the past year has killed hundreds of people, most of them Muslims, and driven more than 140,000 people from their homes.

Latest reports suggest the Trader’s bombing could be linked to yet another source of unrest, the armed ethnic rebel group the Karen National Union (KNU).